离子掺杂氧化锌光催化纳米功能材料的制备及其应用

Preparation and Photocatalytic Application of Ion-Doped ZnO Functional Nanomaterials

氧化锌是一种氧化还原电位高、激子结合能大（~60 meV）、物理和化学稳定性较好、廉价且无毒的半导体光催化剂。本文综述了掺杂氧化锌光催化剂的掺杂离子类型、制备方法、光催化效果及其作用机理。掺杂氧化锌的离子类型主要包括非金属离子单掺杂、金属离子（包括过渡金属离子和稀土金属离子）单掺杂和双离子共掺杂。离子掺杂后可在氧化锌晶格中引入更多的氧空穴或缺陷,为光致氧化反应提供更多的活性位点;或者引入杂质能级,扩大光吸收范围,增强可见光吸收能力。同时,掺杂的离子也可作为电子捕获中心,阻止光生电子-空穴对的复合,从而提高氧化锌光催化剂的性能。此外,文中还对掺杂氧化锌光催化剂在有机污染物降解、抗菌和光催化制氢等方面的应用进行了系统概述,并对其发展趋势作了展望。

Because of its high redox potential, large exciton binding energy （ - 60 meV）, superior physical and chemical stability, inexpensiveness and nontoxicity, ZnO has become one of the most widely investigated semiconductor photocatalysts. In this review, different types of dopants, synthetic methods, photocatalysis and functional mechanism of the doped ZnO nanomaterials are summarized. The doping types include non-metal doping, metal doping （transition metal doping and rare earth metal doping） and co-doping approaches. Through this ion-doping method, oxygen vacancies or defects could be introduced into ZnO lattice, which provides more active sites for the photo-oxidation reaction. On the other hand, the ion-doping approach can produce impurity energy levels in ZnO band gap, leading to the expansion of its light responding region and enhancement of visible-light absorption ability. The doping ion can also work as an electron scavenger inhibiting recombination of electron-hole pairs, thus increases the photocatalytic activity of ZnO nanomaterials. Beside above-mentioned contents, research advances in applications of doped ZnO nanomaterials in fields of degradation of organic pollutants, antibacterial agents and photocatalytic hydrogen production are summarized. And also future developments of the doped nanomaterials are prospected.